Prof. Chittaranjan S Yajnik is a medical scientist from Pune, India who specializes in maternal nutrition and diabetes research. Yajnik is renowned for his research on the topic "thin-fat" Indian, which explains that Indians are adipose (have a high percentage of body fat) despite not being obese by international standards. In his work on the intrauterine programming of diabetes, he successfully demonstrated the potential contribution of maternal micronutrient nutrition to the disease's aetiology. His areas of expertise include patient education, clinical care, and research on the causes of diabetes in India. He is interested particularly in investigating Indians' heightened vulnerability to diabetes and related conditions. He specializes in clinical care, patient education and research in causes of diabetes in India. His special interest is to investigate the high susceptibility of Indians to diabetes and related disorders. Professor Yajnik is a founder member and the Vice President of SNEHA India (Society for Natal Effects on Health in Adults) and a founder member of the International DOHaD Society (Developmental Origins of Health and Disease).